Guide to Wi-Fi

Guide to Wireless and WiFi Systems

Wireless and Network Hardware

Wireless Access Point   

Wireless Access Points (WAP) act as a central transmitter and receiver of the Wireless radio signals for a network.
access point

Wireless router

Most modern small home Wireless routers act as a multi function device. It performs the functions of a “Wireless access point” described above, but also the functions of a “router” and a “network switch”.
A routers job (specifically basic home routers) is to simply pass data, such as web pages and email, between multiple home computers and the internet.
In addition many home routers have a built in DSL modem to connect to Internet services providers over a phone line.

Switch

A Network switch is a device that allows connection of multiple devices together, and allows the transfer of data between the attached devices.

Wireless network interface controller
   
Wireless network interface controllers (WNIC) are used to connect a computer or device to connects to a radio-based computer network.
In simple terms, it allows the connection of a device to a wireless access point.
So when a computer, video game console or smart phone has wireless built in, it has a one of these WNICs built in. Or it could be a USB stick.

WiFi Aerial   

Work in the same way as a TV antenna/aerial.
It is used to increase both the power of the signal being transmitted, and the strength of the signal received.

 

Types of Wireless Signals and Speeds

802.11b aka “B”   

+ lowest cost; signal range is good and not easily obstructed

– slowest maximum speed 11Mbps; home appliances may interfere

802.11a – “A”
   
+ fast maximum speed, 54Mbps; no signal interference from other devices

– highest cost; shorter range signal that is more easily obstructed

802.11g – “G”  

Fast maximum speed, 54-108Mbps; signal range is good and not easily obstructed
appliances may interfere with signal

802.11n “N”
   
Fastest maximum speed, 150-300Mbps, and best signal range; more resistant to signal interference from outside sources.

Bluetooth   

Bluetooth is a wireless technology for exchanging data over short distances. The chip can be plugged into computers, digital cameras and mobile phones.
Using a special radio frequency to transmit data, it creates a short range network. It is very secure and can connect up to eight devices (items of electronic equipment) at the same time.
Mainly used for mobile phones to communicate with each other, with computers and with wireless headsets.

 

Increasing Signal Strength and Range

Better Aerial   

Attaching a more powerful aerial to the access point will give out a stronger signal.
Attaching a more powerful aerial to the computer or device will let it pick up signals better.
Not all routers allow the aerial to be changed. So check your router has a detachable aerial before purchasing.
There are two main types

Omni-directional- Give out a signal in all directions.

Uni-directional – Aims a signal in one particular direction.

Uni-directional signals usual travel further but only in one direction.

Access point upgrade
   
Upgrade your access point or router to either something with MIMO technology which utilises multiple aerials to give a better signal, or to an N capable router.

To fully utilise a “N” capable router all wireless devices should be upgraded to N wireless.

Wireless Repeater
   
A wireless repeater bounces the wireless signal further. It works by receiving the wireless signal than transmitting it again.

It looks the same as an Access point and usually works as an access point too.

Additional Access point
   
If you have a secondary access point you have 2 devices giving a wireless signal. And by placing them in the right location and giving them each a different channel you can transmit over a far greater area than with just one.

The access point has to be connected by a network cable to the router.

You can add even more access points but they have to be setup in a way as not to interfere with each other.

Powerline Wireless   

Technically this is the same as adding an access point. Advantage is there is no need to have a network cable running from the access point all the way back to the router which can be difficult to install cleanly

Using powerline technology this is instead done over the mains cables.

You plug one unit next to the router and the other any where else in the home where you want a wireless signal.